METHOD FOR PREPARING HARD CARBON ANODE OF LITHIUM/SODIUM ION BATTERY BY BIOCHAR

Provided is a method for preparing a hard carbon anode of a lithium/sodium ion battery by biochar, which includes the following steps: S1 biochar pretreatment, S2, preparing a precursor material and S3 pyrolysis carbonization, by a modification of the biochar, setting carbonization temperature and carbonization time, and controlling a cooling rate, so that the obtained biochar generates amorphous carbon after carbonization with low graphitization degree, few surface defects, larger charge-discharge specific capacity, and stable performance in the cycle charging and discharging process; at the same time, the process of the application is relatively simple, and a special complex process is reduced; the present method is suitable for a large-scale industrial production without special adjustment or control of a morphology; and the product performance is relatively good and thus has certain competitive advantages.